Refactor WKT for reuse and speed.

Author: eseglem

.pre-commit-config.yaml

@@ -1,18 +1,18 @@
 repos:
   - repo: https://github.com/psf/black
-    rev: 22.6.0
+    rev: 22.12.0
     hooks:
       - id: black
         language_version: python
 
   - repo: https://github.com/PyCQA/isort
-    rev: 5.10.1
+    rev: 5.12.0
     hooks:
       - id: isort
         language_version: python
 
   - repo: https://github.com/PyCQA/flake8
-    rev: 5.0.4
+    rev: 6.0.0
     hooks:
       - id: flake8
         language_version: python
@@ -26,7 +26,7 @@ repos:
           - toml
 
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v0.971
+    rev: v0.991
     hooks:
       - id: mypy
         language_version: python

geojson_pydantic/geometries.py

@@ -17,6 +17,21 @@
 )
 
 
+def _position_wkt_coordinates(position: Position) -> str:
+    """Converts a Position to WKT Coordinates."""
+    return " ".join(str(number) for number in position)
+
+
+def _position_list_wkt_coordinates(positions: List[Position]) -> str:
+    """Converts a list of Positions to WKT Coordinates."""
+    return ", ".join(_position_wkt_coordinates(position) for position in positions)
+
+
+def _lines_wtk_coordinates(lines: List[List[Position]]) -> str:
+    """Converts lines to WKT Coordinates."""
+    return ", ".join(f"({_position_list_wkt_coordinates(line)})" for line in lines)
+
+
 class _GeometryBase(BaseModel, abc.ABC):
     """Base class for geometry models"""
 
@@ -50,7 +65,11 @@ def _wkt_type(self) -> str:
     @property
     def wkt(self) -> str:
         """Return the Well Known Text representation."""
-        return f"{self._wkt_type}{self._wkt_inset}({self._wkt_coordinates})"
+        return self._wkt_type + (
+            f"{self._wkt_inset}({self._wkt_coordinates})"
+            if self.coordinates
+            else " EMPTY"
+        )
 
 
 class Point(_GeometryBase):
@@ -61,7 +80,7 @@ class Point(_GeometryBase):
 
     @property
     def _wkt_coordinates(self) -> str:
-        return " ".join(str(coordinate) for coordinate in self.coordinates)
+        return _position_wkt_coordinates(self.coordinates)
 
     @property
     def _wkt_inset(self) -> str:
@@ -80,8 +99,7 @@ def _wkt_inset(self) -> str:
 
     @property
     def _wkt_coordinates(self) -> str:
-        points = [Point(coordinates=p) for p in self.coordinates]
-        return ", ".join(point._wkt_coordinates for point in points)
+        return _position_list_wkt_coordinates(self.coordinates)
 
 
 class LineString(_GeometryBase):
@@ -96,8 +114,7 @@ def _wkt_inset(self) -> str:
 
     @property
     def _wkt_coordinates(self) -> str:
-        points = [Point(coordinates=p) for p in self.coordinates]
-        return ", ".join(point._wkt_coordinates for point in points)
+        return _position_list_wkt_coordinates(self.coordinates)
 
 
 class MultiLineString(_GeometryBase):
@@ -112,8 +129,7 @@ def _wkt_inset(self) -> str:
 
     @property
     def _wkt_coordinates(self) -> str:
-        lines = [LineString(coordinates=line) for line in self.coordinates]
-        return ",".join(f"({line._wkt_coordinates})" for line in lines)
+        return _lines_wtk_coordinates(self.coordinates)
 
 
 class LinearRingGeom(LineString):
@@ -160,11 +176,7 @@ def _wkt_inset(self) -> str:
 
     @property
     def _wkt_coordinates(self) -> str:
-        ic = "".join(
-            f", ({LinearRingGeom(coordinates=interior)._wkt_coordinates})"
-            for interior in self.interiors
-        )
-        return f"({LinearRingGeom(coordinates=self.exterior)._wkt_coordinates}){ic}"
+        return _lines_wtk_coordinates(self.coordinates)
 
     @classmethod
     def from_bounds(
@@ -190,8 +202,9 @@ def _wkt_inset(self) -> str:
 
     @property
     def _wkt_coordinates(self) -> str:
-        polygons = [Polygon(coordinates=poly) for poly in self.coordinates]
-        return ",".join(f"({poly._wkt_coordinates})" for poly in polygons)
+        return ",".join(
+            f"({_lines_wtk_coordinates(polygon)})" for polygon in self.coordinates
+        )
 
 
 Geometry = Union[Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon]

tests/test_geometries.py

@@ -22,7 +22,7 @@ def assert_wkt_equivalence(geom: Union[Geometry, GeometryCollection]):
     """Assert WKT equivalence with Shapely."""
     # Remove any trailing `.0` to match Shapely format
     clean_wkt = re.sub(r"\.0(\D)", r"\1", geom.wkt)
-    assert shape(geom.dict()).wkt == clean_wkt
+    assert shape(geom).wkt == clean_wkt
 
 
 @pytest.mark.parametrize("coordinates", [(1.01, 2.01), (1.0, 2.0, 3.0), (1.0, 2.0)])
@@ -51,10 +51,11 @@ def test_point_invalid_coordinates(coordinates):
 @pytest.mark.parametrize(
     "coordinates",
     [
+        # No Z
         [(1.0, 2.0)],
         [(1.0, 2.0), (1.0, 2.0)],
+        # Has Z
         [(1.0, 2.0, 3.0), (1.0, 2.0, 3.0)],
-        [(1.0, 2.0), (1.0, 2.0)],
     ],
 )
 def test_multi_point_valid_coordinates(coordinates):
@@ -83,9 +84,12 @@ def test_multi_point_invalid_coordinates(coordinates):
 @pytest.mark.parametrize(
     "coordinates",
     [
+        # Two Points, no Z
         [(1.0, 2.0), (3.0, 4.0)],
-        [(0.0, 0.0, 0.0), (1.0, 1.0, 1.0)],
+        # Three Points, no Z
         [(1.0, 2.0), (3.0, 4.0), (5.0, 6.0)],
+        # Two Points, has Z
+        [(0.0, 0.0, 0.0), (1.0, 1.0, 1.0)],
     ],
 )
 def test_line_string_valid_coordinates(coordinates):
@@ -111,9 +115,16 @@ def test_line_string_invalid_coordinates(coordinates):
 @pytest.mark.parametrize(
     "coordinates",
     [
+        # One line, two points, no Z
         [[(1.0, 2.0), (3.0, 4.0)]],
+        # One line, two points, has Z
         [[(0.0, 0.0, 0.0), (1.0, 1.0, 1.0)]],
+        # One line, three points, no Z
         [[(1.0, 2.0), (3.0, 4.0), (5.0, 6.0)]],
+        # Two lines, two points each, no Z
+        [[(1.0, 2.0), (3.0, 4.0)], [(0.0, 0.0), (1.0, 1.0)]],
+        # Two lines, two points each, has Z
+        [[(1.0, 2.0, 0.0), (3.0, 4.0, 1.0)], [(0.0, 0.0, 0.0), (1.0, 1.0, 1.0)]],
     ],
 )
 def test_multi_line_string_valid_coordinates(coordinates):
@@ -141,7 +152,9 @@ def test_multi_line_string_invalid_coordinates(coordinates):
 @pytest.mark.parametrize(
     "coordinates",
     [
+        # Polygon, no Z
         [[(1.0, 2.0), (3.0, 4.0), (5.0, 6.0), (1.0, 2.0)]],
+        # Polygon, has Z
         [[(0.0, 0.0, 0.0), (1.0, 1.0, 0.0), (1.0, 0.0, 0.0), (0.0, 0.0, 0.0)]],
     ],
 )
@@ -158,14 +171,36 @@ def test_polygon_valid_coordinates(coordinates):
     assert_wkt_equivalence(polygon)
 
 
-def test_polygon_with_holes():
-    """Check interior and exterior rings."""
-    polygon = Polygon(
-        coordinates=[
+@pytest.mark.parametrize(
+    "coordinates",
+    [
+        # Polygon with holes, no Z
+        [
             [(0.0, 0.0), (0.0, 10.0), (10.0, 10.0), (10.0, 0.0), (0.0, 0.0)],
             [(2.0, 2.0), (2.0, 4.0), (4.0, 4.0), (4.0, 2.0), (2.0, 2.0)],
-        ]
-    )
+        ],
+        # Polygon with holes, has Z
+        [
+            [
+                (0.0, 0.0, 0.0),
+                (0.0, 10.0, 0.0),
+                (10.0, 10.0, 0.0),
+                (10.0, 0.0, 0.0),
+                (0.0, 0.0, 0.0),
+            ],
+            [
+                (2.0, 2.0, 1.0),
+                (2.0, 4.0, 1.0),
+                (4.0, 4.0, 1.0),
+                (4.0, 2.0, 1.0),
+                (2.0, 2.0, 1.0),
+            ],
+        ],
+    ],
+)
+def test_polygon_with_holes(coordinates):
+    """Check interior and exterior rings."""
+    polygon = Polygon(coordinates=coordinates)
 
     assert polygon.type == "Polygon"
     assert hasattr(polygon, "__geo_interface__")
@@ -196,10 +231,18 @@ def test_polygon_invalid_coordinates(coordinates):
         Polygon(coordinates=coordinates)
 
 
-def test_multi_polygon():
-    """Should accept sequence of polygons."""
-    multi_polygon = MultiPolygon(
-        coordinates=[
+@pytest.mark.parametrize(
+    "coordinates",
+    [
+        # Multipolygon, no Z
+        [
+            [
+                [(0.0, 0.0), (1.0, 0.0), (1.0, 1.0), (0.0, 1.0), (0.0, 0.0)],
+                [(2.1, 2.1), (2.2, 2.1), (2.2, 2.2), (2.1, 2.2), (2.1, 2.1)],
+            ]
+        ],
+        # Multipolygon, has Z
+        [
             [
                 [
                     (0.0, 0.0, 4.0),
@@ -216,8 +259,12 @@ def test_multi_polygon():
                     (2.1, 2.1, 4.0),
                 ],
             ]
-        ]
-    )
+        ],
+    ],
+)
+def test_multi_polygon(coordinates):
+    """Should accept sequence of polygons."""
+    multi_polygon = MultiPolygon(coordinates=coordinates)
 
     assert multi_polygon.type == "MultiPolygon"
     assert hasattr(multi_polygon, "__geo_interface__")